Battery-plate.



No. 879,361. PATENTEII' B. 18, 1908.

I W. M. BRODIE.

BATTERY PLATE.

Agrmcnmn FILED 513.15, 1905.

Attest My pfvi/ UNITED STATES PATENT OFFICE.

WILLIAM M. BRODIE, OF WEST ORANGE, NEW JERSEY, ASSIGNOR TO EDISON MANU-FACTURING COMPANY, OF WEST ORANGE, NEW JERSEY, A CORPORATION OF NEW 7 VJERSEY.

BATTERY-PLATE.

Patented Feb. 18, 1908.

Application filed February 15. 1905. Serial Ho. 245.652-

for use in primary batteries and more ar' ticularly those of the Lalandety e in w rich metallic zinc is employed in an a kaline solution, andconsists in the features hereinafter described and claimed.

In the drawings which accompany this ap-- plication, Figures 1 and 2 areside elevation and plan of one form of plate embodying my invention.Fig. 3 is a view similar to Fig. l of a modification. Fig. 4 is asection on the line 44 of Fig. 3, and, Fig. 5 is a section onv the line5-5 of F ig. 3.

In batteries of the type above referred to, the copper oxid plateundergoes chemical change during the operation of the battery, beingreduced to metallic copper. As soon as the entire bulk of the plate or alarge portion thereof has been reduced, the battery loses itsellicicncy, and it is necessary to renew the copper oxid plate. Thecurrent which can be. obtained from such a cell de pends largely uponthe amount of surface presented by the copper oxid plate; that is, 1f wecompare two cells in which the copper oxid plates are of the same weightbut of different shapes, that cell in which the copper oxid plate hasthe greater surface will deliver the greater current-that is, it willhave. a higher discharge rate, though of course the copper oxid [datewill become exhausted the sooner. It is very desirable to secure a highdischarge rate, since this enables one to secure the same current from asmaller or more compact cell. In order to matcriall y increase thesurface of the plate as regards its niass, I endeavored to produce a coper oxid plate having dcep corrugations ormed therein. This material is,however, one whose particles have very slight attraction for cach other,so that in forming battery plates, it is necessarytosubjcct the materialto enormous pressure. In this manner, it has been pos sible heretoforeto produce plates whose sur faces are plane or practically so. dca'vorto make a dccply corrugated plate of and in nearly every case the platewas either ruined during the process of manufacturethat is, 'while beingremoved from the diesor else was possessed of so little strength afterthe baking operations as to be ractically worthless, since it wouldbreak wit 1 ordinary handling. For instance, the entire series ofcorrugations would frequently be stripped from the body of the plate.However, after many experiments, I found that by forming the. dies sothat the tops or projecting portions of the corrugations of one die areopposite the depressions of the corrugations of the other die, and alsoby avoiding abrupt curves and making the corrugations well rounded, itis possible to produce in this manner a deeply corrugated plate ofsullicientstrength for practical use.

It is obvious that a plate f this form will contain more material withina given projected area than a plate having flat faces and the sameeil'cctive thickness, and from this it. results that if such plates besubjected to the same rate of discharge the corrugated plate u ill be oflonger life than the lint plate.

I do not use a binder in making a plate of the material described, as myexperience with binders has been unsatishu-tory, the binders tending toeither destroy, wcakcn, or chemically react upon the plates during thebaking process to which they must be subjected. l have obtainedexcellent rcsults by very slightly dampening the pulverulcnt copper oxidwith a solution of caustic soda. which gives the same enough coln-relu-cto maintain its shape prior to and during the baking operation, whichdrivcs oil the moisture and causes the copper oxid to bccome hard andcoherent, so that it will resist ordinary handling as an article ofcommerce, this use of caustic soda and the baking operation beingcxpcdicnts well known in the art.

The plates invented by me may be in the forms shown in thc drawing.wherein it will be observed that the charzu'lcristics specified as tothe corrugations are present. I hnd in practice that the distance fromone corruln my cui such material I encountered great dilliculties, 1

gallon to nnotlu-r--lhnt is. the distance fr m the top of onecorrugation to the top of the one adjoining. may be one-half inch. whilethe distance from the highest point of a corrugation to the lowest pointis threesixtcculhs of an inch. In the form shown in Figs. 3, 4 and 5,the corrugations are bclow llaving now described my invention, I

declare that hat 1 claiutis:

1. As a new article of manufacture, a.

- strongly coherent, pressed copper oxid plate having corrugationsformed therein of such depth as to materially increase the superficialarea thereof, substantially as set forth.

2. As a new article of manufacture. a strongly coherent, pressed copperoxid plate having corrugations formed in both faces thereof of suchdepth as to materially increase the superficial area thereof,substantially as set forth. Y

3. As a new article of -manufacturc, a strongly coherent, pressed copperoxid plate having corrugations formed in both faces thereof of suchdepth as to materially in crease the superficial area thereof, theelevations of one set of corrugations being directly opposite thedepressions of the other set. substantially as set forth.

4. As a new article of manufacture, a strongly coherent, pressed copperoxid plate having corrugations formed therein of such depth as tomaterially increase the superficial area thereof, the tops and bottomsof said corrugations being well rounded, substantially as set forth.

v5. As a new article of manufacture, a strongly coherent, pressed copperoxid late having corrugations formed in both aces thereof of such depthas to materially increase the superficial area thereof, the tops andbottoms of said corrugations being well rounded and the elevations ofone set of corrugations being directly op )osite the depressions of theother set, suiistantially as set forth.

6. As a new article of manufacture, a strongly coherent, pressed copperoxid plate, having corrugations formed therein below the surfaces of itsupper and lower edges,

substantially as setforth.

7. As a new article of manufacture, a strongly coherent, pressed copperoxid plate having corrugations formed in both faces thereof helow thesurfaces of its upper and lower edges, substantially as set forth.

This specification signed and witnessed this 10th day of February, 1905.

\VILLIAM .\l. BRODIE.

Yitnesses:

Fnaxn ll. Drnn, Axxa P. KLnnn.

Htl

